public interface RecordComparator
RecordEnumeration
to sort and return
records in an application specified order. For example:
RecordComparator c = new AddressRecordComparator(); if (c.compare(recordStore.getRecord(rec1), recordStore.getRecord(rec2)) == RecordComparator.PRECEDES) return rec1; |
Modifier and Type | Field and Description |
---|---|
static int |
EQUIVALENT
EQUIVALENT means that in terms of search or sort order, the
two records are the same. |
static int |
FOLLOWS
FOLLOWS means that the left (first parameter) record
follows the right (second parameter) record in terms of search
or sort order. |
static int |
PRECEDES
PRECEDES means that the left (first parameter) record
precedes the right (second parameter) record in terms of search
or sort order. |
Modifier and Type | Method and Description |
---|---|
int |
compare(byte[] rec1,
byte[] rec2)
Returns
RecordComparator.PRECEDES if rec1 precedes rec2 in
sort order, or RecordComparator.FOLLOWS if rec1 follows
rec2 in sort order, or RecordComparator.EQUIVALENT if rec1
and rec2 are equivalent in terms of sort order. |
static final int EQUIVALENT
EQUIVALENT
means that in terms of search or sort order, the
two records are the same. This does not necessarily mean that
the two records are identical.
The value of EQUIVALENT is 0.
static final int FOLLOWS
FOLLOWS
means that the left (first parameter) record
follows the right (second parameter) record in terms of search
or sort order.
The value of FOLLOWS is 1.
static final int PRECEDES
PRECEDES
means that the left (first parameter) record
precedes the right (second parameter) record in terms of search
or sort order.
The value of PRECEDES is -1.
int compare(byte[] rec1, byte[] rec2)
RecordComparator.PRECEDES
if rec1 precedes rec2 in
sort order, or RecordComparator.FOLLOWS
if rec1 follows
rec2 in sort order, or RecordComparator.EQUIVALENT
if rec1
and rec2 are equivalent in terms of sort order.rec1
- the first record to use for comparison. Within this method,
the application must treat this parameter as read-only.rec2
- the second record to use for comparison. Within this method,
the application must treat this parameter as read-only.RecordComparator.PRECEDES
if rec1 precedes rec2 in
sort order, or RecordComparator.FOLLOWS
if rec1
follows rec2 in sort order, or
RecordComparator.EQUIVALENT
if rec1 and rec2 are
equivalent in terms of sort orderCopyright (c) 2014, Oracle and/or its affiliates. All rights reserved. Use of this specification is subject to license terms.